package heng926;

import java.util.Scanner;

/**
 * @author tmh
 * @date 2024/9/26 18:55
 * @description 已经知道c，且a+b=c(a,b都是整数)，求a*b的最大值是多少
 */
public class T1 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            long num = in.nextInt();
            long result = 0;
            if (num % 2 == 0) {
                long half = num / 2;
                result = half * half;
            } else {
                long a = num / 2;
                long b = num - a;
                result = a * b;
            }
            System.out.println(result);
        }
    }
}
